Just about incidents like the WTC disaster maybe they should hook some device that can let the people in the air traffic control be able to shut off control from the cockpit and it has a screen in the air traffic control and they can control it from there, it would stop a lot of hijacking incidents from being disastorous

For teachers and little kids its always annoying to get chalk all over your fingers so why not just use a holder for your chalk so you don't get all dirty white hands.